1. Field of the Invention
The present invention relates to methods for forming correction patterns, liquid ejecting apparatuses, and correction patterns.
2. Description of the Related Art
Inkjet printers, which are a representative liquid ejecting apparatus, are well known. Inkjet printers are provided with an inkjet-type ejection head for ejecting ink, which is an example of a liquid, from nozzles, and are configured such as to record, for example, images or characters by ejecting ink onto print paper, which is an example of a medium. Among such inkjet printers, there are those that have a function of executing so-called “bidirectional printing,” in which printing is implemented by ejecting ink in both forward and return passes in order to increase the printing speed.
When ejecting ink to form dots on a print paper in order to record, for example, images or characters with such inkjet printers, there are instances in which discrepancies occur between the dot formation positions, in the moving direction of the ejection head, of the dots that are formed in the forward pass, and the dot formation positions, in that moving direction, of the dots that are formed in the return pass in bidirectional printing. These discrepancies between dot formation positions are a cause of deteriorated quality in, for example, the recorded images and characters, and thus it is necessary that these discrepancies are corrected.
One method proposed for correcting such discrepancies between the dot formation positions is a method for forming a correction pattern, which has differences in darkness in the moving direction and which is used for correcting the above-mentioned discrepancies based on these differences in darkness, on print paper by ejecting ink from nozzles provided in an ejection head, and reading the darkness of the correction pattern using a sensor in order to obtain darkness information for correcting the discrepancies (see, for example, Patent Document 1).